Amphoteric surfactants based upon epoxy succinic acid

ABSTRACT

The present invention deals with novel compounds their applications and a process their preparation. The compounds are novel amphoteric surfactants that contain a hydroxyl group and two carboxylic groups per hydroxyl group. The compounds have a unique structure, having multiple carboxyl groups on each amino group. The utility for these novel polymers is as softening, anti-tangle, and conditioning agents for use in personal care, textile and related applications.

1. FIELD OF THE INVENTION

The present invention deals with novel compounds, their applications anda process their preparation. The compounds are novel amphotericsurfactants that contain a hydroxyl group and two carboxylic groups perhydroxyl group. The compounds have a unique structure, having multiplecarboxyl groups on each amino group. The utility for these novelpolymers is as softening, anti-tangle, and conditioning agents for usein personal care, textile and related applications. The properties ofthese novel amphoteric polymeric compositions which makes them wellsuited for these applications is the fact that they are substantive tofibers, hair and skin and also very mild to the skin and eyes.

2. DESCRIPTION OF THE ARTS AND PRACTICES

Aminocarboxylic amphoteric surfactants have been known and usedcommercially for many years. Perhaps the most important early patent onthe production of these materials is U.S. Pat. No. 2,195,974 to Reppe etal. The patent, issued in May 1936 and assigned to I. G. Farben,discloses the reaction of acrylic acid, methacrylic acid and ammonia ororganic amines at temperatures at which amides do not form. The patentdescribed many reaction conditions in addition many solvents weredescribed ranging from water to other protic solvents. Reppe alsodescribes many so-called “acrylic sources”, which are suitable as rawmaterials for preparation of this class of amphoteric surfactants.

The surfactant properties of aminocarboxylic acids and salts arelikewise well known to those skilled in the art. Over the years, thesecompounds have been found to have limited usefulness as foaming agentsand detergents in some applications. The compounds have not enjoyedwider use in other applications, due to the fact the prior art compoundslack compatibility with anionic surface active agents, are not mild whenapplied to the eye and skin

U.S. Pat. No. 3,417,136 issued to Hovden Dec. 17, 1968, attempts todevelop a product with increased water solubility by incorporating anether function into the molecule. Hovden states prior to his invention,the known aminocarboxylic acid surfactant compounds have a lesser watersolubility than is desired in some applications. Further, he states manyof these compounds do not have as great a wetting power as might bedesired for certain applications. This is also a function of watersolubility.

While Hovden's invention solved the difficulty of obtaining a series ofproducts that are more water soluble and have improved wettingproperties, it remained a problem to produce products with the desiredanionic compatibility and mildness and electrolyte compatibility.

OBJECT OF THE INVENTION

It is the object of this invention to produce novel amphoteric compoundsthat have improved are highly substantive to hair, skin and fibers, havelow irritation properties when placed on the skin or in the eyes, andare compatible with anionic surfactants. This improved performancerelates to the fact that the products of this invention (a) containfatty amino groups and (b) contain a poly carboxy functionality whichresults amphoterics with unique solubility, and emulsificationproperties in a variety of solvents. These materials also provide stablecopious foam and much improved detergency properties over traditionalamino proprionates.

Another object of the invention is to provide a novel class ofamphoteric compounds that exhibit outstanding surface-active properties.

Still another object of the invention is a process for the treatment ofskin, hair and fibers with an effective conditioning amount of thecompounds of the invention.

Other objects of the invention will become clear from the disclosure.

THE INVENTION

The compounds of the present invention are poly-carboxy containingamphoteric surfactants. They compounds of the present invention conformto the following structure;

R¹ is selected from the group consisting of alkyl having from 6 to 20carbon atoms and

 R⁴—O—(CH₂)₃—

R⁴ is alkyl having from 6 to 20 carbon atoms;

R² is

M is a cation needed for charge balance and is selected from the groupconsisting of Na, K, Li and H;

R³ is selected from the group consisting of H and

The compounds of the present invention are multi-carboxylates. In oneinstance a di carboxylate that has a secondary amine present. Typical ofthis type of compound is as follows:

In another preferred instance they are tetra carboxylates that have atertiary amine present.

In this latter case the tetra carboxylate results in an amphotericsurfactant that is not sensitive to Ca ion. Standard amphoterics conformto the following structure:

R-N-(CH₂CH₂C(O)OH)₂

These compounds have only two carboxyl groups that branch at nitrogen,lack the hydroxy group and consequently have poor hard water tolerance.

PREFERRED EMBODIMENTS

By properly selecting the number of carbon atoms in the alkyl or alkylether group a product that has the proper balance between water-solubleand oil soluble groups is attained.

In a preferred embodiment R¹ is of alkyl having from 6 to 20 carbonatoms

In a preferred embodiment R¹ is R⁴—O—(CH₂)₃—.

In a preferred embodiment R¹ is M is H.

In a preferred embodiment R¹ is M is Na.

In a preferred embodiment R¹ is M is K.

In a preferred embodiment R¹ is M is Li.

In a preferred embodiment R³ is H.

In a preferred embodiment R³ is

In a preferred embodiment R¹ is of alkyl having 6 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 8 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 10 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 12 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 14 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 16 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 18 carbon atoms.

In a preferred embodiment R¹ is of alkyl having 20 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 6 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 8 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 10 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 12 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 14 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 16 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 18 carbon atoms.

In a preferred embodiment R⁴ is of alkyl having 20 carbon atoms.

EXAMPLES Raw Materials

A. Amines

1. Alkyl Amines

R¹ is of alkyl having from 6 to 20 carbon atoms

Example R¹ 1 C₆H₁₃ 2 C₈H₁₇ 3 C₁₀H₂₁ 4 C₁₂H₂₅ 5 C₁₄H₂₉ 6 C₁₆H₃₃ 7 C₁₈H₃₇8 C₂₀H₄₁

2. Alkyl Ether Amines

Example R⁴  9 C₆H₁₃ 10 C₈H₁₇ 11 C₁₀H₂₁ 12 C₁₂H₂₅ 13 C₁₄H₂₉ 14 C₁₆H₃₃ 15C₁₈H₃₇ 16 C₂₀H₄₁

B. Epoxy Succinate (Disodium cis-epoxysuccinate):

A solution of 23.2g (0.2 mole) of maleic acid in 15 ml distilled waterwas added to a 200 ml beaker. A solution of 12g (0.3 mole) of sodiumhydroxide in 10 ml water, 0.66g (0.02 mole) of sodium tungstate wereadded in the above mixture. The hot solution (heated by neutralization)was brought to a temperature below 65C. A standard pH electrode wasinserted into the solution and 24.5 ml (0.24 mole, 30%) hydrogenperoxide was added all at once.

The reaction began to be observed at 65° C. the reaction is stronglyexothermic. The temperature was held at about 65-70° C. for 45 min.During the reaction period the pH fell from about 5.5 to 2. Aconcentrated sodium hydroxide solution was added dropwise to maintainthe pH about 4.5-5.

After an additional hour at 65° C., the reaction mixture was cooled alittle bit and poured it into 250 ml acetone with stirring. About 35gdisodium cis-epoxysuccinate was precipitated. (Yield about 100%)

Amphoteric Preparation GENERAL PROCEDURE Example 17-32

Mono Functional

In a suitable three neck flask equipped with agitation and thermometer,is added 1000 grams of water, 182.0 grams of disodiumcis-epoxysuccinate. Next, the specified amount of the specified aminereactant (examples 1-16) is added. The reaction mass will thicken asheat is applied. At about 80-90 C the viscosity thins out. Hold at thistemperature 5 to 9 hours. The reaction is complete when the tertiaryamine concentration reaches at least 97% of theoretical. Add enough baseto neutralize the product to a pH of 7 to 8. Addition is exothermic andis controlled by submersion of the flask into a cooling bath. Theproduct is now present in aqueous solution and can be used withoutpurification or can be dried down in a roto-evaporator if desired.

Amine Example Example Grams 17 1 101.0 18 2 129.0 19 3 157.0 20 4 185.021 5 213.0 22 6 247.0 23 7 269.0 24 8 297.0 25 9 147.0 26 10  175.0 2711  203.0 28 12  231.0 29 13  259.0 30 14  293.0 31 15  315.0 32 16 343.0

Example 33-48

Di Functional

In a suitable three neck flask equipped with agitation and thermometer,is added 1000 grams of water, 364.0 grams of disodiumcis-epoxysuccinate. Next, the specified amount of the specified aminereactant (examples 1-16) is added. The reaction mass will thicken asheat is applied. At about 80-90 C the viscosity thins out. Hold at thistemperature 5 to 9 hours. The reaction is complete when the tertiaryamine concentration reaches at least 97% of theoretical. Add enough baseto neutralize the product to a pH of 7 to 8. Addition is exothermic andis controlled by submersion of the flask into a cooling bath. Theproduct is now present in aqueous solution and can be used withoutpurification or can be dried down in a roto-evaporator if desired.

Amine Example Example Grams 33 1 101.0 34 2 129.0 35 3 157.0 36 4 185.037 5 213.0 38 6 247.0 39 7 269.0 40 8 297.0 41 9 147.0 42 10  175.0 4311  203.0 44 12  231.0 45 13  259.0 46 14  293.0 47 15  315.0 48 16 343.0

APPLICATIONS EXAMPLES

The amphoteric compounds of this invention can be formulated intosofteners that are applied directly in aqueous solution by themselves orformulated with anionic, nonionic or amphoteric surfactants and buildersto prepare finished conditioner/detergent systems. The level ofcomposition of the present invention is typically used at a weight ratioto water of about 1:10:000 to 1:20 to soften fabric.

Conditioners and Shampoos using the compositions employ it at 2% to 30%by weight. Anionic surfactants include laurel and stearyl sulfate aswell as alkylbenzene sulfonates, Preferably the sodium salts. Nonionicsurfactants include alkylalkoxylates typically having from 10 to 20carbon atoms in the alkyl group and from 1 to 10 alkylene oxide units(preferably ethylene). Builders include the phosphates STPP and SPP aswell as aluminosilicates.

Wet Comb out Test

A laboratory test is conducted to screen the wet comb properties of arepresentative member of the family of novel compositions. Hair swatchesare purchased from a supply of human hair from the same head. Each testswatch contains 7 grams of hair and is 11 inches in length. The hair istied tightly 1 inch from one end with string. The swatch is pre-cleanedwith a 3% solution of ammonium lauryl sulfate.

Subsequently, the swatch is washed under running tap water. The hair isthen squeezed out and while still damp dipped into a 200-ml solution of0.2% active product. Another rinse is made, then the swatch is blotteddry. The swatch is then treated by holding the hair swatch, combing thehair as rapidly as possible while alternating the side of the swatchcombed. The time needed to get one smooth free stroke without tanglingis recorded. Typical results for the standard quaternary compounds usedin hair conditioning (stearyldimethylbenzyl ammonium chloride) rangefrom 12-14 seconds.

Rinse Conditioner (Wet Comb Out Test)

Product Time in Seconds Example #33 11 Example #47 13Stearyldimethylbenzyl ammonium chloride 12

While the illustrative embodiments of the invention have been describedwith particularity, it will be understood that various othermodifications will be apparent to and can be readily made by thoseskilled in the art without departing from the spirit and scope of theinvention. Accordingly, it is not intended that the scope of the claimsappended hereto be limited to the examples and descriptions set forthhereinabove but rather that the claims be construed as encompassing allthe features of patentable novelty which reside in the presentinvention, including all features which would be treated as equivalentsthereof by those skilled in the art to which the invention pertains.

What is claimed is:
 1. A compound conforming to the following structure:

R¹ is R⁴—O—(CH₂)₃— R⁴ is alkyl having from 6 to 20 carbon atoms; R² is

M is a cation selected from the group consisting of Na, K, Li and H; R³is selected from the group consisting of H and


2. A compound of claim 1 wherein R⁴ is C₆H₁₃.
 3. A compound of claim 1wherein R⁴ is C₈H₁₇.
 4. A compound of claim 1 wherein R⁴ is C₁₀H₂₁.
 5. Acompound of claim 1 wherein R⁴ is C₁₂H₂₅.
 6. A compound of claim 1wherein R⁴ is C₁₄H₂₉.
 7. A compound of claim 1 wherein R⁴ is C₁₆H₃₃. 8.A compound of claim 1 wherein R⁴ is C₁₈H₃₇.
 9. A compound of claim 1wherein R⁴ is C₂₀H₄₁.